Build Assimp from source

thirdparty/assimp/code/.editorconfig

@@ -0,0 +1,8 @@
+# See <http://EditorConfig.org> for details
+
+[*.{h,hpp,c,cpp}]
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_size = 4
+indent_style = space